This proposal outlines a program consisting of three interrelated projects that will utilize the skills of six investigators and the combined resources of the Department of Microbiology, University of Rochester School of Medicine and Dentistry and the Strong Memorial Hospital-Monroe County Health Department Microbiology Laboratories in the study of Neisseria gonorrhoeae. The long-range goals of the project are: (1) identification of an antigen that can be utilized for rapid, accurate diagnosis of N. gonorrhoeae infections; (2) elucidation of the pathobiology of N. gonorrhoeae, including structure of the cell wall, development of a genetic system for analyzing the chromosome of N. gonorrhoeae, andisolation and characterization of viruses which infect N. gonorrhoeae; and (3) development of an attenuated vaccine strain through genetic engineering. Detailed methodology of the various projects are outlined in the proposal.